package IO;

import java.io.*;
import java.util.Scanner;

//实现复制文件,把源文件的每个字节都读出来,写入目标文件中
public class Demo6 {
    public static void main(String[] args) {
        //1.输入路径并校验
        Scanner scanner = new Scanner(System.in);
        System.out.println("请输入源文件的路径: ");
        String srcPath = scanner.next();
        File srcFile = new File(srcPath);
        if (!srcFile.isFile()) {
            System.out.println("源文件路径有误!");
            return;
        }
        System.out.println("请输入目标文件的路径: ");
        String destPath = scanner.next();
        File destFile = new File(destPath);
        if (!destFile.getParentFile().isDirectory()) {
            System.out.println("目标文件的路径有误!");
            return;
        }

        //2.执行复制过程
        try (InputStream inputStream = new FileInputStream(srcFile);
        OutputStream outputStream = new FileOutputStream(destFile)) {
            while (true) {
                //使用缓冲区进行文件复制
                byte[] buffer = new byte[1024];
                //从输入流读取数据到缓冲区
                int n = inputStream.read(buffer);
                System.out.println("n = " + n);
                if (n == -1) {
                    break;
                }
                //将缓冲区的数据写入输出流
                outputStream.write(buffer,0,n);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}
